From the introduction:
Picture having no body, no mind. The only thing holding you up is your soul. You are your soul. Emotion, raw and pure.
Picture the great afterlife. Most souls reunite with the great one spirit, losing their personality, their individuality, but not their being. Like a drop of water entering an ocean. One day, the molecules of water will again be used, but never again as the exact same drop
Picture those that are different. Those that have enough self-love to keep, from rejoining. Those that stay separate. As they live, they gain more and more emotion, and become greater and greater. It is these "ghosts" that existence must worry about.
Ghost Light is a Dark Fantasy game where you (as players) assume the role of ghosts, but not your standard "haunts". You become denizens of a world all but removed from our own. Having no body (mental or physical) you are forced to rely on the one thing still remaining: your emotion. As you grow in emotion, you grow in power, but beware--for emotion can be consuming.